A typical internal combustion engine, installed in a machine, includes a combustion chamber where a mixture of fuel and air ignites to generate combustion gases. These combustion gases causes a piston in the combustion chamber to move up and down (hereinafter referred to as reciprocating motion). Usually, the piston is coupled to a crankshaft, housed within a crankcase, in such a manner that the reciprocating motion of the piston causes the crankshaft to rotate. The rotary motion of the crankshaft is utilized to drive various components of the machine.
In certain scenarios, a fraction of the combustion gases (generated during ignition of fuel and air mixture) leaks past the piston into the crankcase. Hereinafter, such gases that leak into the crankcase have been referred to as blow-by gases. It may be necessary to remove these blow-by gases from the crankcase. Usually, the blow-by gases are removed from the crankcase using crankcase ventilation system. Typically, there exist two types of crankcase ventilation systems namely open crankcase ventilation system and closed crankcase ventilation system. In the open crankcase ventilation system, the blow-by gases are removed from the crankcase and are vented out in to the atmosphere. On the other hand, in the closed crankcase ventilation system, the blow-by gases are fed back into the internal combustion engine through a compressor of the turbocharger. A typical compressor compresses a mixture of the blow-by gases and the fresh air, and feeds it back to the internal combustion engine.
The blow-by gases usually include oil droplets (from the crankcase), and it may be required to filter out the oil droplets prior to entry of the blow-by gases into the compressor. Further, when the machine operates at locations where the atmospheric temperature is below the freezing point, the water vapors in the blow-by gases may condense rapidly to form ice-crystals, on interaction of the blow-by gases with the fresh air (which could be below freezing temperature) in the compressor. The so formed ice-crystals may damage the components of the compressor such as impeller blades.
U.S. Pat. No. 9,003,791 ('791) discloses a compressor that includes a housing. The housing defines an air passage for receiving fresh air. Further, the housing includes a casing treatment chamber that is formed inside the compressor housing. The casing treatment chamber receives blow-by gases from the crankcase of the engine. The casing treatment chamber includes a plurality of first recirculation openings and a plurality of second recirculation openings that are formed along a circumferential direction of the casing treatment chamber at equal intervals. As the first recirculation opening and the second recirculation opening are intermittently formed in the casing treatment chamber, the blow-by gases exiting from these openings do not mix uniformly with the fresh air. Further, as the casing treatment chamber is formed inside the compressor housing, the casing treatment chamber may disrupt the flow of the fresh air in the compressor, which may be undesirable.